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Kalden J, Tessarek C, Sebald K, Figge S, Kruse C, Hommel D, Gutowski J. Electroluminescence from a single InGaN quantum dot in the green spectral region up to 150 K. NANOTECHNOLOGY 2010; 21:015204. [PMID: 19946174 DOI: 10.1088/0957-4484/21/1/015204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present electrically driven luminescence from single InGaN quantum dots embedded into a light emitting diode structure grown by metal-organic vapor-phase epitaxy. Single sharp emission lines in the green spectral region can be identified. Temperature dependent measurements demonstrate thermal stability of the emission of a single quantum dot up to 150 K. These results are an important step towards applications like electrically driven single-photon emitters, which are a basis for applications incorporating plastic optical fibers as well as for modern concepts of free space quantum cryptography.
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Petschnik A, Klatte J, Evers L, Kruse C, Paus R, Danner S. Phenotypic indications that human sweat glands are a rich source of nestin-positive stem cell populations. Br J Dermatol 2009; 162:380-3. [DOI: 10.1111/j.1365-2133.2009.09512.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Wiersig J, Gies C, Jahnke F, Assmann M, Berstermann T, Bayer M, Kistner C, Reitzenstein S, Schneider C, Höfling S, Forchel A, Kruse C, Kalden J, Hommel D. Direct observation of correlations between individual photon emission events of a microcavity laser. Nature 2009; 460:245-9. [PMID: 19587766 DOI: 10.1038/nature08126] [Citation(s) in RCA: 177] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Accepted: 04/28/2009] [Indexed: 11/09/2022]
Abstract
Lasers are recognized for coherent light emission, the onset of which is reflected in a change in the photon statistics. For many years, attempts have been made to directly measure correlations in the individual photon emission events of semiconductor lasers. Previously, the temporal decay of these correlations below or at the lasing threshold was considerably faster than could be measured with the time resolution provided by the Hanbury Brown/Twiss measurement set-up used. Here we demonstrate a measurement technique using a streak camera that overcomes this limitation and provides a record of the arrival times of individual photons. This allows us to investigate the dynamical evolution of correlations between the individual photon emission events. We apply our studies to micropillar lasers with semiconductor quantum dots as the active material, operating in the regime of cavity quantum electrodynamics. For laser resonators with a low cavity quality factor, Q, a smooth transition from photon bunching to uncorrelated emission with increasing pumping is observed; for high-Q resonators, we see a non-monotonic dependence around the threshold where quantum light emission can occur. We identify regimes of dynamical anti-bunching of photons in agreement with the predictions of a microscopic theory that includes semiconductor-specific effects.
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Kremer M, Egaña J, Danner S, Rapoport D, Lavandero S, Mailänder P, Kruse C, Machens H. Use of Pancreas-derived Stem Cells to improve vascularization in skin tissue engineering. J Plast Reconstr Aesthet Surg 2009. [DOI: 10.1016/j.bjps.2009.02.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Aschenbrenner T, Kruse C, Kunert G, Figge S, Sebald K, Kalden J, Voss T, Gutowski J, Hommel D. Highly ordered catalyst-free and mask-free GaN nanorods on r-plane sapphire. NANOTECHNOLOGY 2009; 20:075604. [PMID: 19417425 DOI: 10.1088/0957-4484/20/7/075604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Self-organized and highly ordered GaN nanorods were grown without catalyst on r-plane sapphire using a combination of molecular beam epitaxy and metal-organic vapor-phase epitaxy. AlN nucleation centers for the nanorods were prepared by nitridation of the sapphire in a metal-organic vapor-phase epitaxy reactor, while the nanorods were grown by molecular beam epitaxy. A coalesced two-dimensional GaN layer was observed between the nanorods. The nanorods are inclined by 62 degrees towards the [Formula: see text]-directions of the a-plane GaN layer. The high degree of ordering and the structural perfection were confirmed by micro-photoluminescence measurements.
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Sebald K, Kalden J, Voss T, Gutowski J, Aschenbrenner T, Kunert G, Kruse C, Figge S, Hommel D. Optical properties of GaN nanorods grown catalyst-free on r-plane sapphire. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/pssc.200880945] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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57
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Gust A, Kruse C, Otte K, Kalden J, Meeser T, Sebald K, Gutowski J, Hommel D. A CdSe quantum dot based resonant cavity light-emitting diode showing single line emission up to 90 K. NANOTECHNOLOGY 2009; 20:015401. [PMID: 19417251 DOI: 10.1088/0957-4484/20/1/015401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A II-VI wide-bandgap resonant cavity light-emitting diode is presented. The active region consists of CdSe quantum dots embedded in ZnSSe/MgS barriers, resulting in improved quantum efficiency at elevated temperatures. The resonant cavity is formed by a 14-period bottom distributed Bragg reflector and the semiconductor to air interface on top of the structure. Temperature dependent micro-electroluminescence measurements reveal emission of a single quantum dot up to 90 K. The turn-on voltages are 6 V at 4 K and 4 V at room temperature. These results are promising for the realization of green surface-emitting devices in general, and especially for an electrically driven prospective single photon source operating at room temperature.
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Ciba P, Sturmheit T, Petschnik A, Kruse C, Danner S. In vitro cultures of human pancreatic stem cells: Gene and protein expression of designated markers varies with passage. Ann Anat 2009; 191:94-103. [DOI: 10.1016/j.aanat.2008.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 07/02/2008] [Accepted: 07/18/2008] [Indexed: 01/01/2023]
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Guldner NW, Kruse C, Klapproth P, Großherr M, Noel R, Sievers HH. Bio-technologies for a glandular stem cell cardio-myopexy. Thorac Cardiovasc Surg 2009. [DOI: 10.1055/s-0029-1191681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ciba P, Schicktanz S, Anders E, Siegl E, Stielow A, Klink E, Kruse C. Long-term culture of a cell population from Siberian sturgeon (Acipenser baerii) head kidney. FISH PHYSIOLOGY AND BIOCHEMISTRY 2008; 34:367-372. [PMID: 18958594 DOI: 10.1007/s10695-007-9196-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 12/14/2007] [Indexed: 05/25/2023]
Abstract
In vitro cultures of native fish cell lines are of great importance, both for basic research and applied science. In particular, there is strong demand for long-term growable cell lines from breeding fish, like sturgeon. Here, we describe the culture of cells from Siberian sturgeon (Acipenser baerii) head kidney. The cells have so far been cultured over a period of 12 months (24 passages). Cytochemical and immunocytochemical examination suggests that, in vitro, the cells exhibit markers that are indicative for different cell types. In particular, fat storing cells (adipocytes) were observed, and the expression of cytokeratins and glial fibrilar acidic protein (GFAP) can be concluded on the basis of immuncytochemical analysis. The observation of different morphologies additionally underlines the heterogeneity of the cell population and matches the typical behaviour of in vitro cultures of stem/progenitor cells. Different applications can be imagined.
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Saw C, Ferenci M, Kruse C, Singer M, Wagner H. SU-GG-T-384: Overcoming Challenges in the Implementation of Oncology Information System. Med Phys 2008. [DOI: 10.1118/1.2962136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Kruse C, Figge S, Dartsch H, Tessarek C, Hommel D, Lohmeyer H, Kalden J, Sebald K, Gutowski J. Integration of InGaN quantum dots into nitride-based microcavities. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/pssc.200778736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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63
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Kruse C, Danner S, Rapoport D. Current Stem Cell Technology: Limitations and Realistic Expectations. Eng Life Sci 2008. [DOI: 10.1002/elsc.200820226] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Kruse C, Jost R, Lipschis M, Kopp B, Hartmann M, Hell R. Sulfur-enhanced defence: effects of sulfur metabolism, nitrogen supply, and pathogen lifestyle. PLANT BIOLOGY (STUTTGART, GERMANY) 2007; 9:608-19. [PMID: 17853361 DOI: 10.1055/s-2007-965432] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Evidence from field experiments indicates differential roles of sulfur and nitrogen supply for plant resistance against pathogens. Dissection of these observations in defined pathosystems and controlled nutritional conditions indicates an activation of plant sulfur metabolism in several incompatible and compatible interactions. Contents of cysteine and glutathione as markers of primary sulfate assimilation and stress response show increases in ARABIDOPSIS THALIANA upon infection, coinciding with the synthesis of sulfur-containing defence compounds. Similar increases of thiols were observed with necrotrophic, biotrophic, and hemibiotrophic pathogens. Sulfate supply was found to be neutral or beneficial for tolerance against fungal but neutral for bacterial pathogens under IN VITRO conditions. According to various reports and own observations the effects of nitrogen supply appeared to be neutral or harmful, depending on the pathogen. The activation of sulfur metabolism was a consequence of activation of gene expression as revealed by macroarray analysis of an A. THALIANA/ALTERNARIA BRASSICICOLA pathosystem. This activation appeared to be largely independent from sufficient or optimal sulfate supply and from the established sulfate deficiency response. The data suggest that plant-pathogen interactions and sulfur metabolism are linked by jasmonic acid as signal.
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Guldner NW, Kajahn J, Klinger M, Sievers HH, Kruse C. Autonomously contracting human cardiomyocytes generated from adult pancreatic stem cells and enhanced in co-cultures with myocardial biopsies. Int J Artif Organs 2007; 29:1158-66. [PMID: 17219356 DOI: 10.1177/039139880602901209] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Myocardial regeneration with artificially applied cardiomyocytes is emerging as a promising issue of significant scientific and clinical impact. Nevertheless the source of cells for human cardiomyocyte differentiation especially from adult tissue is still unclear. We hypothesized that human pancreatic stem cells may differentiate into cardiomyocyte-like cells and may increase in number when co-cultured with myocardial tissue. Adult stem cells were harvested from pancreatic tissue of patients undergoing operative procedures including the pancreas. The cells were selected, cultured and passaged. To promote self-differentiation into cardiomyocytes, human pancreatic stem cells were co-cultered with biopsies of human myocardium. After co-culture and breeding, cells were phenotyped as well with respect to RNA, protein and cardiomyocyte specificity at the electron-microscopic level.Pancreatic stem cells have already differentiated spontaneously into cardiomyocyte-like cells performing netlike cell clusters with rare but distinct multilocular cellular autonomous contractions with a frequency of about 20 beats per minute. The number of contracting areas however could be enhanced by co-culture with human myocardial biopsies. On RNA and protein levels as well as in electron-microscopy, evidence for cardiomyocyte specificity is shown. To the best of our knowledge this is the first report demonstrating the feasibility of generating autonomously contracting cardiomyocyte-like cells from adult human pancreatic stem cells and their enhancement by myocardial co-culture. This procedure might prove to be an alternative source and method for myocardial regenerative medicine.
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Guldner NW, Kruse C, Kajahn J, Klinger M, Sievers HH. Autonomously contracting human cardiomyocytes generated from adult human pancreatic stem cells preferably after cocultivation with human myocardium. Thorac Cardiovasc Surg 2007. [DOI: 10.1055/s-2007-967427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Danner S, Kajahn J, Geismann C, Klink E, Kruse C. Derivation of oocyte-like cells from a clonal pancreatic stem cell line. Mol Hum Reprod 2006; 13:11-20. [PMID: 17114208 DOI: 10.1093/molehr/gal096] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Adult pancreatic stem cells (PSCs) are able to differentiate spontaneously in vitro into various somatic cell types. Stem cells isolated from rat pancreas show extensive self-renewal ability and grow in highly viable long-term cultures. Additionally, these cells express typical stem cell markers such as Oct-4, nestin and SSEA-1. Although differentiation potential is slightly decreasing in long-term cultures, it is possible to keep cell lines up to passage 140. Clonal cell lines could be established from different passages and showed similar characteristics. Remarkably, one clonal cell line, generated from passage 75, showed deviant properties during further culture. Clonal cells formed aggregates, which built tissue-like structures in suspension culture. These generated 3D aggregates produced permanently new cells at the outside margin. Released cells had remarkable size, and closer examination by light microscopy analysis revealed oocyte-like morphology. A comparison of the gene expression patterns between primary cultures of passages 8 and 75, the clonal cell line and the produced oocyte-like cells (OLCs) from tissue-like structures demonstrated some differences. Expression of various germ cell markers, such as Vasa, growth differentiation marker 9 and SSEA-1, increased in the clonal cell line, and OLCs showed additionally expression of meiosis-specific markers SCP3 and DMC1. We here present a first pilot study investigating the putative germ line potential of adult PSCs.
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Ciba P, Danner S, Geismann C, Petschnik A, Guldner N, Kruse C. Gerichtete Differenzierung adulter Stammzellen. CHEM-ING-TECH 2006. [DOI: 10.1002/cite.200650417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
Due to the bowel's poor tolerance of hypoxia, intestinal malperfusion presents as a grave disease with high mortality. The intensivist is confronted with this condition in association with other underlying diseases, in the course of surgery, during application of medication or associated with invasive therapy. In a critical care setting, the non-occlusive mesenteric ischemia (NOMI) is of increasing importance. Since critical care patients often lack clinical symptoms, special attention is required and one main factor of the patient's prognosis is early diagnosis. This review summarizes pathophysiology and diagnostic aspects and the range of therapeutic and preventive measures.
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Kruse C, Steffensen R, Varming K, Christiansen OB. A study of HLA-DR and -DQ alleles in 588 patients and 562 controls confirms that HLA-DRB1*03 is associated with recurrent miscarriage. Hum Reprod 2004; 19:1215-21. [PMID: 15070884 DOI: 10.1093/humrep/deh200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Previous studies have demonstrated an association between recurrent miscarriage (RM) and the maternal HLA-DRB1*01 and -DRB1*03 alleles. The primary aim of the present study was to confirm or reject the hypothesis about this association in a larger case-control study. METHODS HLA-DRB1, -DQA1 and -DQB1 genotyping was carried out by the PCR-sequence-specific primer (SSP) method in 354 patients with unexplained RM and 202 fertile controls. These results were combined with the results from a previous study of 234 RM patients and 360 controls. RESULTS The prevalence of patients with HLA-DRB1*03 was significantly increased compared with controls [odds ratio (OR) = 1.4, 95% confidence interval (CI) = 1.1-1.9, P = 0.01, P corrected for the number of comparisons (Pc) = 0.02]. In patients with at least four previous miscarriages or with secondary RM, the association became even stronger (OR = 1.8, 95% CI = 1.3-2.5, P = 0.0005, Pc = 0.004; and OR = 1.8, 95% CI = 1.3-2.5, P = 0.0007, Pc = 0.006, respectively). There was no significant difference between patients and controls with regard to HLA-DRB1*01. CONCLUSION The HLA-DRB1*03 allele or genes in linkage disequilibrium with it confer susceptibility to RM.
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Kruse C, Varming K, Christiansen OB. Prospective, serial investigations of in-vitro lymphocyte cytokine production, CD62L expression and proliferative response to microbial antigens in women with recurrent miscarriage. Hum Reprod 2003; 18:2465-72. [PMID: 14585903 DOI: 10.1093/humrep/deg469] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Lymphocytes from pregnant women with unexplained recurrent miscarriage (RM) may be characterized by a T-helper type 1-dominated cytokine production and a higher proliferative response to microbial recall antigens compared with normal pregnant women. METHODS Serial blood samples were taken from 14 women with RM (at least three previous consecutive miscarriages) during the first 14 weeks of pregnancy, and one blood sample was taken from 15 control women in gestational weeks 7-8. Of the 14 pregnant RM patients, four produced a live birth and 10 miscarried. Lymphocytes were in-vitro-stimulated by mitogens, allogeneic cells and microbial antigens, and the production of a series of cytokines, the proliferative responses and lymphocytic expression of CD62L (which may be a marker of T-helper type 2 lymphocytes) were measured. RESULTS Repeated measurements of cytokine production were reproducible during the first trimester. The proliferative responses to herpes simplex and tetanus antigens were increased, and the ratio of CD62L-/CD62L+ expressing CD4+CD45RO+ lymphocytes was decreased in patients compared with controls (P = 0.01, P < 0.01 and P < 0.01 respectively). CONCLUSION The results of the in-vitro assays used were reproducible in serial testing during pregnancy. The importance of CD62L expression on lymphocytes for RM and the relevance of the maternal response to microbial antigens during pregnancy should be further explored.
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Kruse C, Willkomm D, Gebken J, Schuh A, Stossberg H, Vollbrandt T, Müller PK. The multi-KH protein vigilin associates with free and membrane-bound ribosomes. Cell Mol Life Sci 2003; 60:2219-27. [PMID: 14618268 PMCID: PMC11138841 DOI: 10.1007/s00018-003-3235-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The-multi-KH domain protein vigilin has been identified by ex vivo experiments as both a tRNA- and/or mRNA-binding protein. We show here that in vitro under conditions previously shown to allow tRNA binding, recombinant vigilin also binds to selected mRNA species and ribosomal RNA. An in vivo link of vigilin to mRNA and rRNA was elucidated by several approaches. (i) Coexpression/costimulation of vigilin was found with many other proteins independently of whether their mRNA was translated on free or membrane-bound ribosomes. (ii) A close codistribution of vigilin with free ribosomes was seen in the cytoplasm while nucleoli were a major organelle of vigilin accumulation in the nucleus. (iii) Furthermore, free and membrane-bound ribosomes can be enriched for vigilin which suggests that this binding does not depend on the class of mRNA translated. Therefore, we suggest that vigilin does not distinguish between free or membrane-bound ribosomes but is generally necessary for the localization of mRNAs to actively translating ribosomes.
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Rohwedel J, Kügler S, Engebrecht T, Purschke W, Müller PK, Kruse C. Evidence for posttranscriptional regulation of the multi K homology domain protein vigilin by a small peptide encoded in the 5' leader sequence. Cell Mol Life Sci 2003; 60:1705-15. [PMID: 14504658 PMCID: PMC11138898 DOI: 10.1007/s00018-003-3134-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Vigilin, a K homology (KH) protein has been found in all eukaryotic species studied. It has a unique structure of 14-15 consecutively arranged KH domains which apparently mediate RNA-protein binding. Cloning and sequencing of the mouse vigilin cDNA confirmed that the amino acid sequences of vertebrate vigilins are highly conserved and contain conserved sequence motifs of nuclear import and export sequences. The human and murine vigilin mRNAs carry two alternatively spliced 5' exons. In the 5' leader region of one of the splice variants, variant 1A, we found an upstream open reading frame (uORF) highly conserved between mouse and human. Here we present for the first time evidence that a 13 amino acid long peptide encoded by this uORF is an inhibitor of vigilin expression operating on a posttranscriptional level. We propose that the two structurally different 5' leader sequences of the human vigilin mRNA are involved in the regulation of vigilin biosynthesis.
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Hilgendorf I, Gellersen O, Emmrich J, Mikkat U, Rohwedel J, Krammer HJ, Müller PK, Kruse C. Estradiol has a direct impact on the exocrine pancreas as demonstrated by enzyme and vigilin expression. Pancreatology 2002; 1:24-9. [PMID: 12120263 DOI: 10.1159/000055788] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Estrogen receptors have been found in the exocrine pancreas; however, the exact role of estrogen in pancreatic enzyme synthesis and secretion remains to be elucidated. Vigilin, a multi-KH domain protein, is part of a tRNA-containing ribonucleoprotein complex and may be a suitable marker for stimulation of the translational machinery. In the present study, we investigated the influence of estradiol and compared it to CCK on the expression of vigilin, trypsin and amylase in rat pancreatic acini. METHODS Acini were isolated and incubated with CCK or estradiol. The change in amylase and trypsin levels in the medium and in cell extracts were determined using a photometric method. The change in vigilin mRNA and protein expression were determined by RT-PCR and Western blotting, respectively. RESULTS Treatment of isolated exocrine pancreatic cells with estradiol caused stimulation of amylase and trypsin production and inhibition of secretion, while treatment with CCK showed only a minor effect on enzyme production and resulted mainly in a stimulation of secretion. Further we found an increase in vigilin mRNA and protein expression in acini stimulated with both CCK-8 and estradiol. CONCLUSION Our data suggest that estradiol may play a role in inducing exocrine enzyme production but not secretion, and that vigilin, as a marker for translational activity, is stimulated in parallel to the pancreatic enzymes: amylase and trypsin.
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Hviid TV, Hylenius S, Hoegh AM, Kruse C, Christiansen OB. HLA-G polymorphisms in couples with recurrent spontaneous abortions. TISSUE ANTIGENS 2002; 60:122-32. [PMID: 12392506 DOI: 10.1034/j.1399-0039.2002.600202.x] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The etiology of a fraction of recurrent spontaneous abortions (RSA) may involve immunological mechanisms. Aberrant profiles of Th1 and Th2 cytokines have been observed which are not present in uncomplicated pregnancies. Studies of classical HLA class I and II antigens in relation to RSA have not been conclusive. Furthermore, these antigens are not expressed in the placenta with the exception of HLA-C. However, HLA-G is expressed on especially invasive cytotrophoblasts and exists in both membrane and soluble forms. HLA-G may be involved in materno-fetal tolerance. Therefore, 61 RSA couples (with three or more spontaneous abortions) and 47 fertile control couples were HLA-G genotyped by direct DNA sequencing and analyzed for specific polymorphisms. No statistically significant differences were observed in the distribution of HLA-G alleles between controls and RSA couples, however, 15% of the RSA women carried the HLA-G*0106 allele compared to 2% of the control women. The 14 bp deletion polymorphism in exon 8 was investigated separately. There were a greater number of heterozygotes for the 14 bp polymorphism in the group of fertile control women than expected, according to Hardy-Weinberg equilibrium. Furthermore, the HLA-G alleles without the 14 bp sequence were prominent in the RSA males in contrast to the RSA women in whom alleles including the 14 bp sequence were frequently observed, especially as homozygotes. These results are discussed in relation to two hypotheses concerning HLA-G and RSA. A hypothesis of HLA-G histo-incompatibility between fetus/placenta and the mother was not supported by the data. Another hypothesis concerned certain HLA-G alleles associated with an altered expression profile of HLA-G isoforms or reduced expression of certain HLA-G isoforms.
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